=\(\frac{\left(e^2-2e.m+m^2-e^2-2e.m-m^2\right).\left(y^2-2y+1-y^2-2y-1\right)}{a.16.n.h}.\frac{e}{u^{-1}}\)
= \(\frac{-4e.m.\left(-4y\right)}{a.16.n.h}.\frac{e}{u^{-1}}\)
=\(\frac{16e.m.y}{16a.n.h}.\frac{e}{\frac{1}{4}}\)
=\(\frac{e.m.y}{a.n.h}.e.u=\frac{e.m.y.e.u}{a.n.h}\)